Estudos comparativos prévios com inclusão de lesões de bifurcação selecionadas sugerem ausência de benefício de implante eletivo de dois versus stent único. No entanto, a aplicabilidade do técnica provisional parece ser dependente da complexidade da lesão de bifurcação. A área luminar da lesão após tratamento percutâneo, conforme medida pelo ultrassom intracoronário, tem demonstrado valor preditivo significante na evolução tardia dos pacientes submetidos a ICP. Os objetivos desta análise foram avaliar as dimensões luminares de lesões de bifurcação coronária complexas tratadas por ICP, conforme a análise pelo ultrassom, e correlacionar os achados com os resultados imediatos e tardios. Também objetivou-se identificar preditores angiográficos e ultrassonográficos de falência do ramo lateral nos diferentes passos do tratamento e seguimento. Entre maio de 2008 e agosto de 2009, 59 pacientes portadores de lesão de bifurcação complexa, com comprometimento significativo (estenose > 50%) dos dois ramos e lesão no ramo lateral extendendo-se além do óstio, foram abordados inicialmente com pré-dilatação do ramo lateral, a qual foi realizada com sucesso (estenose < 50%, fluxo TIMI 3, sem dissecção) em 54 pacientes (91,5%). Esse pacientes foram então randomizados para tratamento com stent único (estratégia provisional) (n = 27) versus stent duplo (n = 27). Durante o procedimento, 6 pacientes alocados no grupo stent único apresentaram falência do tratamento no ramo lateral (estenose residual >50%, fluxo TIMI < 3 ou dissecção), sendo que, 5 pacientes receberam stent adicional no ramo lateral para otimizar o resultado angiográfico. Ao final do procedimento, os valores médios e desvios padrão (DP) da área mínima do lúmen no óstio do ramo lateral (desfecho primário) foram 3,37 (1,62) mm2 no grupo stent único versus 5,50 (1,41) mm2 no grupo stent duplo (p < 0,001), conforme a alocação randômica. No seguimento angiográfico de 9 meses, as taxas de reestenose no ramo lateral foram 21,7% no grupo stent único versus 4% no grupo stent duplo (p = 0,06), sendo que, todas as recorrências envolveram a localização ostial. Considerando-se o tratamento recebido, a taxa de reestenose no ramo lateral foi significantemente maior nos pacientes tratados com stent único versus stent duplo (27,8% versus 3,3%, p = 0,01). Os preditores de falência da estratégia provisional foram: excêntricidade da lesão (p = 0,02), área mínima do lúmen (p = 0,08) e diâmetro mínimo do lúmen no óstio do ramo lateral (p = 0,06), extensão da lesão (p = 0,09) e percentual de estenose (p = 0,07) do ramo lateral. Com relação a reestenose angiográfica no ramo lateral, os preditores foram: área mínima do lúmen no óstio do ramo lateral ao final do procedimento (p = 0,03), tratamento com stent duplo (p = 0,02), diâmetro mínimo do lúmen (p = 0,03) e percentual de estenose (p = 0,02) no óstio do ramo lateral ao final do procedimento, ganho imediato no óstio do ramo lateral (p = 0,09) e diâmetro de referência do ramo lateral (p = 0,03). Estes resultados sugerem que lesões de bifurcação coronária complexas beneficiam-se de tratamento percutâneo com abordagem inicial com estratégia de dois stents, sendo que, tal benefício esteve relacionado a obtenção de maior área luminar no óstio do ramo lateral. / Previous comparative studies including selected bifurcation lesions have shown no advantage of elective double stenting implantation versus single stenting. However, the applicability of the provisional technique appears to be dependent on the bifurcation lesion complexity. The lesion luminal area after percutaneous treatment, as assessed by intravascular ultrasound, has demonstrated significant predictive value in the late follow-up of patients undergoing PCI. The objectives of this analysis were to evaluate the lesion luminal dimensions of complex coronary bifurcation lesions, as assessed by intravascular ultrasound, and to correlate such findings with acute and late outcomes. Also, it was aimed to identify angiographic and intravascular ultrasound predictors of side branch failure throughout the procedural steps and follow-up. Between may 2008 and august 2009, 59 patients with complex bifurcation lesions, including significant involvement (> 50% stenosis) of both branches and side branch lesion length extending from its ostium, were approached initially with side branch predilatation, which was successful (< 50% stenosis, TIMI 3 flow, no dissection) in 54 patients (91.5%). These patients were then randomized for treatment with single stenting (provisional strategy) (n = 27) versus double stenting (n = 27). During procedure, 6 patients allocated in the single stenting arm presented side branch failure (> 50% residual stenosis, TIMI flow < 3 or dissection), given that 5 patients received an additional stent in the side branch in order to optimize the angiographic result. At final procedure, the mean value and standard deviation (SD) for minimum lumen area at the side branch ostium (primary endpoint) were 3.37 (1.62) mm2 in single stenting versus 5.50 (1.41) mm2 in double stenting (p < 0.001), according to the randomized allocation. In the angiographic follow-up at 9 months, the restenosis rates in the side branch were 21.7% in single stenting versus 4% in double stenting (p = 0.06), given that all recurrences involved the ostial location. Considering the treatment received, the side branch restenosis rate was significantly increase among patients treated with single stenting versus double stenting (27.8% versus 3.3%, p = 0.01). The predictors of provisional strategy failure were: lesion eccentricity (p = 0.02), minimum lumen area (p = 0.08) and minimum lumen diameter in the side branch ostium (p = 0.06), lesion length (p = 0.09) and percent diameter stenosis (p = 0.07) of the side branch. Regarding angiographic restenosis in the side branch, predictors were: minimum lumen area in the side branch ostium at final procedure (p = 0.03), treatment with double stenting (p = 0.02), minimum lumen diameter (p = 0.03) and percent diameter stenosis (p = 0.02) in the side branch ostium at final procedure, acute gain at the side branch ostium (p = 0.09) and side branch reference diameter (p = 0.03). These results suggest that complex coronary bifurcation lesions may benefit from a primary percutaneous approach with double stenting strategy, given that most such benefit was associated with a larger lumen area obtained at the side branch ostium.

La bifurcation coronaire est un site privilégié d’athérosclérose. Jusqu’alors aucune des techniques de stenting provisionnel percutanées avec juxtaposition de ballons n’a démontré de bénéfice clinique. Ces échecs peuvent être expliqués par le non-respect de la géométrie fractale des bifurcations qui pourtant doit toujours guider la revascularisation (correction de la malapposition et optimisation de l’ostium de la branche collatérale). Fort de ce constat, nous avons imaginé une nouvelle technique séquentielle et simple, en 3 temps, le rePOT, associant Proximal Optimizing Technique (POT) initial, ouverture de la branche collatérale et POT final. Son évaluations s’est voulue progressive en 4 étapes : 1) concept, 2) preuve expérimentale de concept, 3) confirmation des bénéfices mécaniques in vivo, et 4) validation clinique. Dans ce travail nous avons donc d’abord expérimentalement démontré la supériorité du résultat mécanique final du rePOT par rapport aux techniques non séquentielles de provisional stenting (manuscrit # 1). Ainsi, le rePOT effondre la malapposition globale du stent, conserve la circularité proximale physiologique et optimise l’obstruction ostiale résiduelle de la branche accessoire. Ces excellents résultats sont confirmés indépendamment du design ou de la composition des stents (manuscrits # 2, 4). Nous avons par ailleurs démontré l’importance de chacune des 3 étapes du rePOT: POT initial (manuscrit # 1), ouverture de SB et POT final (manuscrit # 3). Enfin, fort de ces démonstrations expérimentales, nous avons confirmé in vivo avec mesures OCT itératives à la fois les excellents résultats expérimentaux et la bonne évolution clinique à moyen terme (manuscrit # 5). Ce travail démontre donc étape par étape, de l’expérimentale à la clinique, l’ensemble des bénéfices de cette nouvelle technique séquentielle de stenting provisionnel "rePOT", devenue une référence en Europe dans la revascularisation percutanée des bifurcations coronaires / Coronary bifurcations are a preferential location for atherosclerosis development. Until now, no technic with balloons juxtaposition demonstrated a clinical benefit in percutaneous coronary bifurcation revascularization by provisional stenting (with 1 stent). Successive failures could be explained by the absence of respect of the bifurcations fractal geometry, which need to be systematically followed during all revascularization (correction of the malapposition and optimization of the side branch ostium). Thus, we imagined a new technique, simple and sequential, in 3 steps, named rePOT. It is combining initial Proximal Optimizing Technique (POT), side-branch opening and final POT. We proposed a demonstration in 4 steps : 1) concept, 2) experimental proofs of concept, 3) confirmation of the clinical benefits in vivo, and 4) clinical validation. In this work, we experimentally demonstrated the superiority of the final mechanical results of the rePOT compared to all non-sequential provisional stenting (manuscript # 1). Thus, rePOT decreased stent global malapposition, maintained the initial proximal circularity and optimized the final ostial side branch obstruction. These excellent results were confirmed independently of stent design or material (manuscripts # 2, 4). Moreover, we demonstrated the specific benefits of each steps of the rePOT : initial POT (manuscript # 1), SB opening, and final POT (manuscript # 3). Finally, we confirmed in vivo, with serial OCT analysis, these excellent mechanical results and the good clinical outcome at mid-term. (manuscript # 5). Thank to this step by step demonstration, from experimental to clinic, we confirmed all benefits of this new provisional stenting sequential technique "rePOT". Thereby, before the last step of the demonstration, rePOT became a reference in Europe for the percutaneous revascularization of coronary bifurcations

Estudos comparativos prévios com inclusão de lesões de bifurcação selecionadas sugerem ausência de benefício de implante eletivo de dois versus stent único. No entanto, a aplicabilidade do técnica provisional parece ser dependente da complexidade da lesão de bifurcação. A área luminar da lesão após tratamento percutâneo, conforme medida pelo ultrassom intracoronário, tem demonstrado valor preditivo significante na evolução tardia dos pacientes submetidos a ICP. Os objetivos desta análise foram avaliar as dimensões luminares de lesões de bifurcação coronária complexas tratadas por ICP, conforme a análise pelo ultrassom, e correlacionar os achados com os resultados imediatos e tardios. Também objetivou-se identificar preditores angiográficos e ultrassonográficos de falência do ramo lateral nos diferentes passos do tratamento e seguimento. Entre maio de 2008 e agosto de 2009, 59 pacientes portadores de lesão de bifurcação complexa, com comprometimento significativo (estenose > 50%) dos dois ramos e lesão no ramo lateral extendendo-se além do óstio, foram abordados inicialmente com pré-dilatação do ramo lateral, a qual foi realizada com sucesso (estenose < 50%, fluxo TIMI 3, sem dissecção) em 54 pacientes (91,5%). Esse pacientes foram então randomizados para tratamento com stent único (estratégia provisional) (n = 27) versus stent duplo (n = 27). Durante o procedimento, 6 pacientes alocados no grupo stent único apresentaram falência do tratamento no ramo lateral (estenose residual >50%, fluxo TIMI < 3 ou dissecção), sendo que, 5 pacientes receberam stent adicional no ramo lateral para otimizar o resultado angiográfico. Ao final do procedimento, os valores médios e desvios padrão (DP) da área mínima do lúmen no óstio do ramo lateral (desfecho primário) foram 3,37 (1,62) mm2 no grupo stent único versus 5,50 (1,41) mm2 no grupo stent duplo (p < 0,001), conforme a alocação randômica. No seguimento angiográfico de 9 meses, as taxas de reestenose no ramo lateral foram 21,7% no grupo stent único versus 4% no grupo stent duplo (p = 0,06), sendo que, todas as recorrências envolveram a localização ostial. Considerando-se o tratamento recebido, a taxa de reestenose no ramo lateral foi significantemente maior nos pacientes tratados com stent único versus stent duplo (27,8% versus 3,3%, p = 0,01). Os preditores de falência da estratégia provisional foram: excêntricidade da lesão (p = 0,02), área mínima do lúmen (p = 0,08) e diâmetro mínimo do lúmen no óstio do ramo lateral (p = 0,06), extensão da lesão (p = 0,09) e percentual de estenose (p = 0,07) do ramo lateral. Com relação a reestenose angiográfica no ramo lateral, os preditores foram: área mínima do lúmen no óstio do ramo lateral ao final do procedimento (p = 0,03), tratamento com stent duplo (p = 0,02), diâmetro mínimo do lúmen (p = 0,03) e percentual de estenose (p = 0,02) no óstio do ramo lateral ao final do procedimento, ganho imediato no óstio do ramo lateral (p = 0,09) e diâmetro de referência do ramo lateral (p = 0,03). Estes resultados sugerem que lesões de bifurcação coronária complexas beneficiam-se de tratamento percutâneo com abordagem inicial com estratégia de dois stents, sendo que, tal benefício esteve relacionado a obtenção de maior área luminar no óstio do ramo lateral. / Previous comparative studies including selected bifurcation lesions have shown no advantage of elective double stenting implantation versus single stenting. However, the applicability of the provisional technique appears to be dependent on the bifurcation lesion complexity. The lesion luminal area after percutaneous treatment, as assessed by intravascular ultrasound, has demonstrated significant predictive value in the late follow-up of patients undergoing PCI. The objectives of this analysis were to evaluate the lesion luminal dimensions of complex coronary bifurcation lesions, as assessed by intravascular ultrasound, and to correlate such findings with acute and late outcomes. Also, it was aimed to identify angiographic and intravascular ultrasound predictors of side branch failure throughout the procedural steps and follow-up. Between may 2008 and august 2009, 59 patients with complex bifurcation lesions, including significant involvement (> 50% stenosis) of both branches and side branch lesion length extending from its ostium, were approached initially with side branch predilatation, which was successful (< 50% stenosis, TIMI 3 flow, no dissection) in 54 patients (91.5%). These patients were then randomized for treatment with single stenting (provisional strategy) (n = 27) versus double stenting (n = 27). During procedure, 6 patients allocated in the single stenting arm presented side branch failure (> 50% residual stenosis, TIMI flow < 3 or dissection), given that 5 patients received an additional stent in the side branch in order to optimize the angiographic result. At final procedure, the mean value and standard deviation (SD) for minimum lumen area at the side branch ostium (primary endpoint) were 3.37 (1.62) mm2 in single stenting versus 5.50 (1.41) mm2 in double stenting (p < 0.001), according to the randomized allocation. In the angiographic follow-up at 9 months, the restenosis rates in the side branch were 21.7% in single stenting versus 4% in double stenting (p = 0.06), given that all recurrences involved the ostial location. Considering the treatment received, the side branch restenosis rate was significantly increase among patients treated with single stenting versus double stenting (27.8% versus 3.3%, p = 0.01). The predictors of provisional strategy failure were: lesion eccentricity (p = 0.02), minimum lumen area (p = 0.08) and minimum lumen diameter in the side branch ostium (p = 0.06), lesion length (p = 0.09) and percent diameter stenosis (p = 0.07) of the side branch. Regarding angiographic restenosis in the side branch, predictors were: minimum lumen area in the side branch ostium at final procedure (p = 0.03), treatment with double stenting (p = 0.02), minimum lumen diameter (p = 0.03) and percent diameter stenosis (p = 0.02) in the side branch ostium at final procedure, acute gain at the side branch ostium (p = 0.09) and side branch reference diameter (p = 0.03). These results suggest that complex coronary bifurcation lesions may benefit from a primary percutaneous approach with double stenting strategy, given that most such benefit was associated with a larger lumen area obtained at the side branch ostium.